A Fremont music teacher accused of taking "up-skirt" photos of a woman on an escalator last month at a Seattle airport has been charged with one count of voyeurism.

Prosecutors in King County, Wash., say Christopher T. Wilhite, 33, took several photos of a woman he noticed while passing through a security checkpoint for a flight to Oakland on June 6. Wilhite told investigators he had "a sudden impulse" to snap pictures up the woman's dress as he stood a few steps below her, according to court filings.

A witness said he heard Wilhite's shutter click and saw the woman wrestling with him over the camera.

Officials at the Fremont Unified School District had not been informed of the charges. They confirmed Wilhite taught music in an after-school program in the district for about five years, including last year. His annual contract was not renewed for the 2010-11 school year, said Superintendent Jim Morris.

Morris said the district would open an independent investigation.

"In the case of an employee where we have charges like this, it's our responsibility to follow up for the safety of the children," Morris said.